Original Text
Sun Tzu said: There are five types of fire attacks. The first is to burn enemy soldiers. The second is to burn their supplies. The third is to burn their equipment and stores. The fourth is to burn their arsenals. The fifth is to burn their supply lines and transport routes. To carry out a fire attack, certain conditions must be met, and materials for the attack must be prepared in advance. The timing must be chosen carefully, with favorable days selected. Timing refers to dry weather; favorable days are when the moon is in the constellations of Sagittarius, Pegasus, Leo, and Corvus. Whenever the moon is in these constellations, it is a time when winds will rise.
When using fire to attack the enemy, always adapt troop deployment flexibly based on the changing circumstances caused by the five situations above. If setting fire inside the enemy camp, send troops outside early to coordinate. If the enemy camp is already on fire but the enemy remains calm, wait patiently and do not attack hastily; once the fire rages, decide based on the situation—attack if possible, stop if not. Alternatively, set fire from outside the enemy camp, requiring no internal coordination, only the right timing. When setting fire from upwind, never attack from downwind. If the wind blows long during the day, it tends to stop at night. In commanding an army, one must understand how to flexibly apply these five forms of fire attack and follow natural laws to seize the right moment.
Therefore, using fire to assist an attack makes victory clear and easy; using water to assist an attack strengthens the offensive. But water can only cut off the enemy's formations, communications, and supply lines, not destroy their troops and military supplies like fire can.
If you win a battle, capture the enemy's territory and cities, but fail to consolidate the victory and neglect to reward your troops in a timely manner, it is dangerous—this is called "wasteful delay." Therefore, a wise sovereign must carefully consider this, and a capable general must treat it with seriousness. Do not act if it brings no benefit to the state; do not deploy troops if victory is not assured; do not wage war unless absolutely necessary. A sovereign should not start a war out of momentary anger, nor should a general order an attack out of temporary rage. Act only when it serves the long-term interests of the state, and cease when it does not. Anger can turn back to joy, and rage can turn back to delight, but a nation once destroyed cannot be restored, and the dead cannot be brought back to life. Thus, a wise sovereign must be cautious about war, and a capable general must remain vigilant against rash action—these are the fundamental principles for preserving the state and safeguarding the army!
Commentary
Sun Wu stated that these five methods of fire attack were repeatedly employed by commanders in later wars. However, in his chapter on fire attack, Sun Wu also introduced an important military philosophy: the need for "caution in war." Because fire attack is highly destructive—whether it be people or supplies, once burned, they are gone forever. Therefore, Sun Tzu said: "Fire attack" is merely an auxiliary means of "military attack." This embodies the idea of "leveraging"—using all available objective conditions to strengthen oneself and strike the enemy.
Example Interpretation
Lu Xun burned the Shu army's connected camps.
When it comes to fire attacks, people immediately think of the Battle of Red Cliffs, where Zhou Yu's single blaze destroyed Cao Cao's 800,000-strong army—undeniably formidable. Yet, another fire attack during the Three Kingdoms period is equally renowned.
During the Three Kingdoms period, Wu killed Guan Yu. When Liu Bei learned of this, he was overwhelmed with grief and fury. Ignoring the earnest advice of Zhuge Liang and others, he personally led over 700,000 troops out of Shu to attack Wu. The Shu army advanced eastward, winning over ten consecutive battles with soaring morale, reaching the Yiling and Xiaoting areas, penetrating over five to six hundred miles into Wu's heartland. Panic spread throughout Eastern Wu. Sun Quan adopted Kan Ze's suggestion and appointed the young general Lu Xun as Grand Commander of the forces. Lu Xun, well-versed in the art of war, took command in a time of crisis. He correctly analyzed the situation, recognizing that Liu Bei's momentum was at its peak and that he held the high ground, making it difficult for Wu to attack. Faced with Liu Bei's fierce offensive, he decided to implement a strategic retreat to observe the changes. He ordered all passes and strongholds to be firmly defended and forbade any troops from engaging in battle. This greatly dissatisfied the generals of Eastern Wu, who were eager to fight for revenge. These battle-hardened commanders mocked Lu Xun as a timid scholar. However, with the emperor's sword of authority in his hand, they had no choice but to obey. The Wu army completely withdrew from the mountainous terrain. As a result, the Shu army found it difficult to deploy across the five to six hundred miles of mountainous area, falling into a passive position—unable to fight, with their troops weary and morale dampened.
It was the height of the scorching summer. The Shu army, having traveled a long distance, was both exhausted and overheated. Liu Bei, unable to capture the city after a prolonged siege, had no choice but to set up camp near the forested mountains, planning to launch an attack in the autumn. Lu Xun saw that the Shu army had connected their wooden barriers and set up camp stretching seven hundred li in length, which played right into his hands. Such an encampment, linking the front and rear, was indeed solid, but it had a fatal weakness: it was highly vulnerable to fire. Once a fire broke out, there would be no way to rescue the troops. Lu Xun had exactly hoped for the Shu army to camp in this manner, so he could display his full capabilities. At that time, both Wei ruler Cao Pi and Zhuge Liang, who was far away in Chengdu guarding the main base, had foreseen this. Zhuge Liang was too late to send word, while Cao Pi intended to launch a surprise attack on Jiangdong when Wu achieved a major victory and pursued the enemy.
The moment had come, but Lu Xun did not immediately strike. Instead, he first launched a probing attack to lull the enemy into complacency. He sent General Chunyu Dan with 5,000 troops to assault the enemy camp—the first offensive since Wu’s defensive stand—resulting in a crushing defeat. Victorious, Liu Bei grew even more contemptuous of Lu Xun and let down his guard. The next night, as Lu Xun’s main force advanced, the Shu camp sensed an omen, but Liu Bei dismissed it: “We wiped them out last night; would they dare come again?” Lu Xun set fire to the front and rear of the main camp. The flames, driven by the wind, spread rapidly, throwing Shu troops into chaotic flight. Lu Xun’s forces attacked from all sides, routing the Shu army with countless dead and wounded. Fortunately, Zhao Yun, arriving from Sichuan, rescued Liu Bei, who fled to Baidi City. After this great calamity, Liu Bei fell gravely ill and ultimately died in Baidi City.
This is the Battle of Yiling between Wu and Shu, hailed by Mao Zedong as a classic example of the weak overcoming the strong.